Until now, green building has focused on the big, exciting renewable energy features. The solar panels. The wind turbines. The underground geothermal heating and cooling units. Not to knock these innovative ways to produce home energy (in fact, we’ve got a “House & Home” column on home wind power in this very issue), but they demand a lot of up-front investment to achieve less household emissions. And some are even beginning to argue that the currently accepted green building standard, LEED (Leadership in Energy and Environmental Design), administered by the U.S. Green Building Council, does not go far enough in requiring that benchmarks be met not only in materials and design, but also in indoor air quality, (see “The Question of LEED,”).

Indoor air quality, it turns out, is a major feature of passive houses, which boast the most aggressive standards for energy efficiency in the world. The design took root in Germany but is slowly making inroads into the U.S. building market—and the basic concept is simple. Instead of solar, wind or other green accoutrements, passive houses don’t require much electricity for heating and cooling. That’s because they are insulated to the point of being nearly airtight, not just in the roof and walls but even between the foundation and ground. A heat-recovery system inside a passive home’s ventilation system makes sure needed heat is captured and used, even as fresh outdoor air continually circulates through. Once built, a passive home needs little more than body heat to keep it warm—and for hot climates, the super-thick insulation keeps the muggy air from getting in. There are more than 15,000 homes, schools and buildings built to passive house standards in Europe; in the U.S. there are just over a dozen. But the trend is catching on—as a way to slice not only household emissions, but associated energy bills as well.

If only other environmental challenges were so simply addressed. Or if only, argue the more than 80 leaders, professors, writers, activists and visionaries in the book Moral Ground (Trinity University Press), we felt a moral imperative to address them. We selected two among the collection of thought-provoking essays that attempt through reasoned argument, personal anecdote and even poetry, to move people beyond knowing what is bad for the earth and doing something about it—whether for future generations or their own self-interest.

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